Olefin polymers are used in a wide variety of products, from sheathing for wire and cable to film. Olefin polymers are used, for instance, in injection or compression molding applications, in extruded films or sheeting, as extrusion coatings on paper, for example photographic paper and digital recording paper, and the like. Improvements in catalysts have made it possible to better control polymerization processes and, thus, influence the properties of the bulk material. Increasingly, efforts are being made to tune the physical properties of plastics for lightness, strength, resistance to corrosion, permeability, optical properties, and the like, for particular uses. Chain length, polymer branching and functionality have a significant impact on the physical properties of the polymer. Accordingly, novel catalysts are constantly being sought in attempts to obtain a catalytic process for polymerizing olefins which permits more efficient and better-controlled polymerization of olefins.
The use of late transition metal complexes as catalysts for olefin polymerization has recently been reviewed by Ittel et al. (Chem. Rev. 2000, 100, 1169). Notwithstanding the many advances described therein, there remains a need for new late transition metal catalysts and processes with improved productivities under the elevated temperatures and pressures of commercial reactor operating conditions. New catalysts and processes for these purposes are described herein.